JP3048984B2 - Sealing device and sealing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for sealing a passage between two conduits arranged in an injection mold, and heating the mold in a cavity of the mold in a cycling operation at a high pressure. The present invention relates to a method and an apparatus for guiding a molten resin.

[0002]

2. Description of the Related Art In the design of an injection molding machine or an injection molding die,
It is of great interest to avoid leakage of high temperature, high pressure molten resin materials. For example, the critical leakage area (cr
The iticalleakage area is between the injection nozzle of the injection molding machine and the sprue bushing of the mold. Generally, leakage of molten resin from an injection molding machine occurs at a boundary (contact area) between a manifold and a nozzle mold or between a nozzle mold and a cavity mold.

[0003] Injection molding manifolds usually consist of a large block of runner blocks in communication with an injection nozzle located adjacent to the cavity of the mold. For example, the high pressure of the molten resin flowing at a high temperature and the relative thermal expansion of the material cause a large problem that the runner block slides sideways with respect to the injection nozzle and the molten material moving from the runner block to the injection nozzle leaks. . Therefore, the sealing of the molten resin passage between the injection nozzle and the internal passageway located in the runner block or manifold is a serious design problem, especially if the leak occurs, the injection process must be stopped. .

[0004]

Although various sealing methods and elements have been developed, they do not satisfactorily solve the problem of leakage, especially at the interface (contact area) between the manifold and the nozzle mold. .

[0005] In known designs of injection molds, a small pre-load is applied between the manifold and the nozzle at ambient or cold conditions. Given the inherent thermal expansion of the manifold, the added preload provides sufficient compression between the parts to maintain a seal between the manifold and the nozzle or other passages in the system. be able to.
However, if the compressive force due to the preload is too small, resin leakage will occur, but excessive compression may cause permanent deformation (permanent setting) in the steel manifold or damage to the nozzle housing. is there. Also, the effect of the preload is reduced by the long-term periodic injection molding operation, increasing the risk of leakage.

[0006] In response to these design ideas, resin (resin)
Some improvements have been made using different methods and means to prevent the leakage of spills.

[0007] US Patent 4,5, owned by Schad
No. 88,367 discloses a thermal expansion element for sealing resin flow through a passage between a manifold passage and an injection nozzle, a thermal expansion element having an undercut to provide an additional elastic sealing, and adding elasticity. A thermal expansion element having a spring element that enhances sealing performance is disclosed. The thermal expansion element is a manifold,
Allows relative movement between the thermal expansion element and the nozzle.

[0008] US Pat. No. 5,
No. 374,182 uses a spring that deflects as the nozzle body and air piston housing expand due to a temperature increase. The seal uses a Belleville style disc spring assembled on an insulating sleeve. As the manifold is heated, the disc spring unit absorbs the thermal expansion and prevents overstress on the nozzle housing or residual distortion of the steel sheets that make up the manifold. This structure is an excellent leak prevention measure for many injection molding machines with relatively low injection pressures. US Patent No. 5,374,182
The No. 1 disc spring system is purely axially perpendicular to the interface (contact area) between the nozzle and the manifold plate.
A load in the axial direction is applied to the flange of the nozzle housing to create a sealing force. When an axial sealing force is applied, the sealing stress peaks at the point of contact between the spring and the nozzle, whereas the sealing stress distribution significantly decreases from the sealing stress peak toward the molten resin passage. . At higher injection pressures, this improved structure does not effectively prevent molten resin from leaking outside the passage.

That is, FIG. 10 shows US Pat. No. 5,374,18.
2 shows the sealing device disclosed in No. 2. The sealing device comprises a hot runner manifold 10 and a manifold channel 12, and the injection nozzle 14 has a nozzle channel 16 adjacent to the manifold channel 12. The injection nozzle 14 includes a shoulder 18 adjacent to the manifold 10, and two disc spring type disc spring units 20 for sealing a boundary (contact area) between the nozzle passage 16 and the manifold passage 12. I have. As the hot runner manifold 10 is heated, the disc spring unit 20 absorbs thermal expansion and prevents excessive stress on the nozzle housing or residual distortion of the sheet steel constituting the hot runner manifold 10, thereby improving the leakage prevention characteristics. Show. However, the disc spring system of FIG. 10 applies a purely axial load to the nozzle shoulder 18 perpendicular to the boundary between the nozzle passage 16 and the manifold passage 12. The upper graph 22 of the hot runner manifold 10 in FIG. 10 shows the sealing stress distribution at the boundary and adjacent surface between the nozzle passage 16 and the manifold passage 12, wherein the sealing stress (sealing force) is the hot runner manifold 10.
It shows a significant decrease towards the molten resin path relative to the peak achieved at the point of contact between the nozzle and the nozzle shoulder 18. Therefore, when the injection pressure is high, this apparatus cannot effectively prevent the leakage of the molten resin.

US Pat. No. 5,507,637, owned by Schad et at., Discloses a resin mounted at a manifold and surrounding a nozzle housing at a boundary (contact area) between the manifold and the nozzle. Discloses a hermetic clamp ring that prevents the leakage of spills. The lateral clearance remaining between the clamp ring and the nozzle is
te) allows lateral sliding of the manifold and clamp ring without affecting the alignment of the nozzle tip with respect to te).

The structural concept of the aforementioned US Pat. Nos. 4,588,367, 5,374,182 and 5,507,637 is very progressive and slides between the manifold and the nozzle housing. Use the boundary (contact area). As the manifold heats and expands, it slides across the nozzle housing, which is held in counter bores in the cavity plate. This allows
Independent of the temperature of the manifold, the nozzle tip position can be maintained in proper alignment with the mold gate. However, at the sliding interface (contact area) between the nozzle and the manifold, it is difficult to completely seal the passage between the two-part conduits using the sealing means disclosed in the aforementioned U.S. Pat. Cannot achieve a sealing stress distribution with a peak adjacent to

Accordingly, a primary object of the present invention is to provide an improved seal for sealing the passage between two passages of an injection molding apparatus, particularly between the passage for the injection nozzle and the passage for the hot runner manifold. It is to provide a method and a sealing device.

[0013] It is another object of the present invention to provide an improved sealing method and apparatus capable of obtaining a sealing stress distribution having a peak adjacent to conducts or passageways as described above. Is to do.

[0014] Other objects and advantages of the present invention will become apparent from the following description.

[0015]

According to the present invention, the above objects and advantages can be easily attained.

The sealing device according to the present invention is provided adjacent to the injection molding machine and communicates with each other at the contact area (54) and conducts two conduits for guiding the pressurized molten resin.
ts) (42, 50) and a sealing device (52) for generating an oblique sealing force at the contact area (54) to seal the contact area (54) between the two conducting paths (42, 50). Prepared, 2
Passageways between two conducting paths (42, 50)
Seal. In the embodiment of the present invention, in particular, one of the two conductive paths (42, 50) is a conductive path (42) for the injection nozzle (30), and the other of the two conductive paths (42, 50) is , A conductive path (5) for the hot runner manifold (32) adjacent to the conductive path (42) for the injection nozzle (30).
0). The injection nozzle (30) has a shoulder (44) adjacent to the hot runner manifold (32). The sealing device (52) is a deflecting sealing element (52) that generates a sealing force that is inclined at the contact area (54). The shoulder (44)
It has an inner portion adjacent to the conduit (42) for the injection nozzle (30), and the deflectable sealing element (52) has a greater sealing stress on the inner portion of the shoulder (44) adjacent to the conduit (42). Occurs. The deflection sealing element (52) has a first thickness (T
1) and a first thickness (T).
1) a second inner portion having a smaller second thickness (T2). The second inner portion has a curved inner portion. The deflection sealing element (52) forms at least in part an angle (α) of between 5 ° and 30 ° with respect to the radial surface of the conduit (42) for the injection nozzle (30). The deflection sealing element (52) may be a disc-shaped member. In particular, the sealing stress distribution is
The conduction path (42) and the contact area (5) of the injection nozzle (30)
It has a peak adjacent to 4). In addition, the sealing device (5
Insulation means (53, 55, 57, 59) adjacent to 2) may be included. Insulation means (53, 55, 57, 59)
Is an insulating ring (53), an insulating sleeve (55) or a coated or solid sleeve (57, 59). If an insulating ring (53) is used, the sealing device (52) is located on top of the insulating ring (53). Insulation sleeve (5
5) is used as an extension of the sealing device (52). The sheath or solid sleeve (57, 59) is
Attached to the nozzle housing (34) outside of 2) and / or adjacent to the sealing device (52).

The two conduction paths (4) provided in the injection molding machine
The sealing method of the present invention for sealing the passage between (2, 50)
The contact area (54) for guiding the pressurized molten resin and
Providing two conductive paths (42, 50) forming a channel, and generating an inclined sealing force at the contact area (54) to seal the contact area (54) between the two conductive paths (42, 50). And a step of performing. In the embodiment of the present invention, preferably, one of the two conductive paths (42, 50) is a conductive path (42) for the injection nozzle (30) and the two conductive paths (4, 50).
The other of the two conduits (2, 50) is a conduit (50) for the hot runner manifold (32) adjacent to the conduit (42) for the injection nozzle (30).
Sealing the contact area (54) between the two conduits (42, 50) by means of a sealing device (52) generating a sealing force inclined at the contact area (54) between them. Furthermore, providing a shoulder (44) in the injection nozzle (30) adjacent to the conduit (42) for the injection nozzle (30); 5
2) adjacent to the shoulder (44).
The shoulder (44) is a conducting path (42) for the injection nozzle (30).
And an outer portion spaced from the conduit (42) for the injection nozzle (30), and the deflectable sealing element (52) for the conduit (42) for the injection nozzle (30).
Generating a large sealing stress on the inner side of the shoulder (44) adjacent to the upper side. The sealing device (52) is provided with the injection nozzle (3).
5 ° to 30 ° with respect to the radial surface of the conduction path (42) for 0)
(52) that at least partially forms the angle (α) of the deflection sealing element. Desirably, the sealing stress distribution has a peak adjacent to the conduit (42) and the contact area (54) of the injection nozzle (30).

Other features of the present invention will become apparent from the following description.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a sealing device and a sealing method according to the present invention will be described below with reference to FIGS.

In the embodiment of FIG. 1, a hot tip hot runner injection nozzle 30 cooperates with a hot runner manifold block 32 to introduce high pressure molten resin into a mold cavity (not shown). The injection nozzle 30 can be of any suitable construction, such as, for example, a valve gate or an edge gate, which does not affect the construction and effect of the present invention. The injection nozzle 30 includes a nozzle body or nozzle housing 34 having a nozzle tip 36 at the end aligned with a mold cavity gate 38 for introducing molten resin into a mold cavity (not shown). Typically, the nozzle housing 34 is surrounded by a heating element 40 to maintain an optimal temperature of the molten resin flow flowing through the nozzle channels 42 to the mold cavities. The nozzle housing 34 has an upper flange or shoulder 4 that is maintained in direct contact with the hot runner manifold block 32.
4 to prevent leakage at the boundary area 54 between the nozzle housing 34 and the hot runner manifold block 32. The manifold 32 is located between the mold cavity plate 46 and the mold back plate 48 and provides a number of internal manifold conduits 50 that guide the molten resin to the required number of injection nozzles 30.
including. As clearly shown in FIG.
Is directly adjacent and fluidly connected to a nozzle conduit 42 and guides the molten resin from the manifold conduit 50 to the nozzle conduit 42. According to the present invention, in order to prevent the leakage of the molten resin of the injection pressure flowing from the manifold passage 50 to the nozzle passage 42, the deflection sealing element 52 that generates a strong elasticity by the high-strength steel is provided by the injection nozzle 3.
0, which creates a strong sealing force which is inclined towards the boundary area (contact area) 54 between the nozzle passage 42 and the manifold passage 50. As will be described later, the special structure of the deflection sealing element 52 can be changed,
On the boundary area 54 between the zero and the manifold conduit 50,
It is important that the deflection sealing element 52 generates an inclined sealing force. As shown in FIG. 1, the deflection sealing element 52 abuts the nozzle shoulder 44 and is disposed in a cylindrical (columnar) recess 56 machined in the upper portion of the mold cavity plate 46.

The deflecting sealing element 52, which constitutes the deflecting ring, creates an oblique sealing force and provides a nozzle passage 42 and a manifold passage 50 over a wide operating temperature and injection pressure range.
Maintain a sealed contact between Also, the cavity plate 46
The deflection sealing element 52 may be located within the nozzle housing 34. Unlike prior art devices, the sealing force generated by the sealing device of the present invention is responsive to an initial preload according to temperature gradients and injection pressures, and to subsequent subsequent loads caused by mold operating conditions and factors. In addition, unlike conventional systems, the sealing force generated by the sealing element of the present invention has a maximum value adjacent to nozzle passage 42 and manifold passage 50, as evidenced by sealing stress distribution curve 60 in FIG. To produce a sealing stress distribution that reaches. This is a significant advantage and improvement in preventing leakage. As shown in FIG. 4, a boundary area (contact area) 54 is formed on the upper surface of the nozzle shoulder 44 around the nozzle passageway 42, and around the boundary area 54, the nozzle shoulder 44 contacts the hot runner manifold block 32. An annular recess is formed so as to prevent the boundary area 54 from forming on the nozzle shoulder 44 as shown in FIG.
May be formed on the entire upper surface of the substrate.

As shown in the embodiment of FIG. 1, there is a radial close contact between the deflecting sealing element 52 and the nozzle shoulder 44, resulting in a strong contact between the injection nozzle 30 and the hot runner manifold block 32. The maximum sealing force is transmitted from the deflecting sealing element 52 to the contact area 54 between the nozzle passage 42 and the manifold passage 50 along the radial direction preferentially.

Of course, the sealing device of the present invention can be effectively used in other conduit connections of an injection molding device, for example, in other manifold connections where leakage of molten resin can be a problem.

Details of a preferred embodiment of the sealing element 52 are shown in FIG. The sealing element 52 has a substantially flat surface with an outer surface 62 having a first diameter D1 and a first thickness T1, and a first inner surface 64 having a second diameter D2 smaller than the first diameter D1. It is a ring or a disk. Further, the sealing element 52 comprises a ramp 66 having a third diameter D3 smaller than the second diameter D2 and a second thickness T2 smaller than the first thickness T1. Inner surface 64 is preferably rounded end 68
And an inner inclined portion 66 having The sealing or deflecting element may have a shape other than a disc, for example, square, hexagonal or any other desired non-circular profile. Smooth outer surface 62
Has substantially the same diameter as the cylindrical recess 56.

As shown in FIG. 2, the inclined portion 66 forms an angle α of preferably 5 ° to 30 ° with respect to the radial surface of the nozzle passage 42, and forms an angle α between the nozzle passage 42 and the manifold passage 50. An inclined sealing force is ensured for the contact area 54 between them.

In the embodiment of FIG. 3, the deflection sealing element 52
Has an external thread 70 and is screwed into a corresponding cylindrical recess 72. This facilitates the installation and removal of the deflection sealing element 52 during assembly or operation.

FIGS. 5 and 6 show a modified embodiment of the deflection sealing element 52. A flat disk-shaped element (disk-lik
The e-element 74 also produces a sloping sealing force, achieving the sealing stress distribution shown by the distribution curve 76 having a peak adjacent to the nozzle passage 42. On the other hand, the flat disk-shaped element 78 shown in FIG. 6 has a main body portion 80 and an annular tip 82 facing upward with respect to the main body portion 80, and has a peak adjacent to the conduction path as shown by a distribution curve 84. To achieve a sealing stress distribution having

The deflection sealing element 52 can be formed from various materials or combinations of materials and is ultimately selected based on special molding conditions. Preferably, the deflection element (sealing element) 52
Is made of a high heat conductive material such as high strength steel. The nozzle housing 34 is made of copper (Cu) or copper beryllium (Cu-B).
e), and the deflection element (sealing element) 52 may be formed of a material having a lower thermal conductivity than the material of the nozzle housing 34, for example, titanium (Ti) or a titanium alloy. In some cases, this configuration further enhances the reliability of the seal, as a force is applied when the large radial thermal expansion of the nozzle is limited by the small thermal expansion of the deflection ring 52 surrounded by the cold template. be able to. In addition, the deflection ring 52 may include a core portion made of steel and a skin portion (or only a heat insulating material coating layer) made of a low thermal conductivity material (heat insulating material). Of course, other additional components (options) may be used.

In operation, an interference fit is formed between sealing ring 52 and nozzle shoulder 44. The tight radial fit between the ring 52 and the nozzle shoulder 44 maintains an interference fit over a wide range of operating conditions, such as, for example, temperature and pressure changes.

This initial interference fit is initially formed at room temperature and produces a large sloping force component which is directed towards the boundary between the two channels to be sealed. This initial sealing force has sufficient strength to seal the hot runner manifold block 32 and the nozzle housing 34 even when the molding process is started from a room temperature by mistake.

The initial interference fit eliminates the need to tightly control the pre-loading of the entire hot runner system in order to ensure an effective sealing operation. During the application of the injection molding pressure, the temperature gradient and the circulating injection pressure create an additional force between the nozzle and the sealing ring 52. Unlike known sealing elements, the deflecting sealing ring 52 of the present invention responds to the operating conditions of the mold with increasing sealing force with respect to the passage to be sealed with increasing temperature and injection pressure.

Thus, without causing a leakage problem,
Very wide temperature and pressure operating ranges can be processed. As long as the sealing force slopes towards the passageway between the two channels, the sealing ring 5
There is no need to strictly control the specific geometry and tolerances between 2 and the cylindrical (cylindrical) recess. In addition, the present invention is responsive to changes in operating conditions, especially temperature gradients.

Experiments have shown that when the proper material is selected and the interference fit is achieved at low temperatures, about 36,000 psi per square meter.
It has been found that effective sealing forces occur for the following injection pressures and temperature changes of ± 50 ° C.

Of course, the result is a radial sealing force,
The sealing ring may be varied to other geometries within the parameters that generate the required sealing force in both cold and hot conditions. The sealing force has a double effect, one is to slightly deform the upper surface of the nozzle shoulder. The second is a passage 4 to be sealed between the hot runner manifold block 32 and the nozzle housing 34.
Immediately adjacent to the outer surface of 2,50 is to produce a sealing stress distribution that reaches a maximum.

Also, one or more elements may be used in addition to the sealing element 52, such as a ceramic ring, a titanium ring, or other low thermal conductivity materials, for example, to improve thermal conduction in the area (contact area). Is also good.

In the contact area between the mold manifold and the nozzle, more precisely in the contact area around the inlet of the nozzle, the temperature of the melt (molten resin) caused by the low temperature of the mold plate is prevented. To this end, the present invention uses insulation means located in this area, such as coatings, sleeves and / or rings, as shown in FIGS.

As clearly shown in FIG.
In the template adjacent to the inlet 43, there is provided an insulating ring 5 made of an insulating material such as, for example, any known suitable ceramic, titanium, titanium alloy, Vespel or the like.
3 are arranged. Thus, the deflection sealing ring 52 according to the present invention is located on top of the insulation ring 53, and in a preferred embodiment the insulation ring 53 has the additional function of precisely positioning the nozzle on the template. In this embodiment, the sealing ring 5
2 and the insulating ring 53 do not cooperate functionally.

In another embodiment shown in FIG. 8, for example, any ceramic, titanium, titanium alloy, Vespel (Ve
An insulating sleeve 55 made of any of the previously known suitable materials, such as spel.RTM., cooperates with the deflection sealing ring 52. More precisely, the insulating sleeve 55 is used as an extension of the sealing ring 52 and, optionally, to place both the sealing ring 52 and the nozzle on the template.

In another embodiment shown in FIG.
7, 59 are sheathed or solid sleeves or separate elements that abut the outer side of the sealing ring 52 or the nozzle housing 34 as shown, also formed of a suitable known material as described above. Is done. The two sleeves 57, 59 and the equally acting covering area can be used both or either, depending on what is to be manufactured and treated. If an insulating coating is used as the insulating means 57 and / or 59, one additional component (optional) is a ceramic such as, for example, alumina (aluminum oxide), zirconia (zirconium oxide), titanium oxide or aluminum titanate. A heat insulating thin film consisting of Depending on the application,
These coatings may be formed on the inner part of the nozzle channel 42, more precisely on the channel surface of the melt (molten resin). In some cases, a thin-film protective layer made of a wear-resistant material may be formed on the heat-insulating layer (heat-insulating coating). In this regard, using a TiN (titanium nitride) thin film or a carbon thin film such as diamond gives good results.
In another embodiment, the thermal barrier coating can be formed by spraying a suitable known layer, such as, for example, a coating comprising ceramic. Good results can be achieved with zirconia (zirconium oxide) sprayed at a thickness of 7.62 mm (0.300 inches) or less. When using a heat insulating layer, a wear-resistant protective layer may be subsequently formed. In this respect, nickel (N
Known materials such as i), titanium (Ti), tungsten carbide (WC) or molybdenum (Mo) can be used favorably.

The present invention is not limited to the examples shown and described above, but these examples merely describe the best mode for carrying out the present invention. It should be understood that there is room for changes in size, component arrangement, and operational details. Rather, the invention is intended to cover all modifications that come within the scope defined by the spirit of the invention and the appended claims.

[0041]

As described above, according to the present invention, the leakage of the molten resin is ensured in the contact area between the two conductive paths for guiding the molten resin without causing damage or permanent distortion to the hot runner manifold and the injection nozzle. Since this can be prevented, the injection molding can be performed smoothly.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an injection molding apparatus according to the present invention.

FIG. 2 is a sectional view of a sealing element of the injection molding apparatus of FIG. 1;

FIG. 3 is a sectional view showing a modified embodiment of the sealing element of the injection molding apparatus of FIG. 1;

FIG. 4 is a cross-sectional view showing a sealing element-conduction path contact region of FIG. 1 and a sealing stress distribution thereof.

FIG. 5 is a cross-sectional view showing a sealing element-conducting path contact area and its sealing stress distribution for a modified embodiment.

FIG. 6 is a cross-sectional view showing a sealing element-conduction path contact area and its sealing stress distribution for another modified embodiment.

FIG. 7 is a cross-sectional view illustrating the use of an insulated nozzle placement ring independent of a deflection sealing ring according to the present invention.

FIG. 8 is a sectional view showing the use of a deflection sealing ring according to the invention in combination with a heat insulating sleeve.

FIG. 9 is a sectional view showing a state in which a heat insulating sleeve is used independently of a deflection sealing ring according to the present invention.

FIG. 10 is a cross-sectional view of a conventional sealing device and a graph showing a sealing stress distribution curve thereof.

[Explanation of symbols]

30 ··· Injection nozzle, 32 ·· Hot runner manifold, 44 ·· Shoulder, 42, 50 ·· Conduction path, 52 ·
· Sealing devices (deflection sealing elements), 54 · · · contact areas,

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Rajang Puri Canada El 5R 3G 9 Baguette Cresent, Mississauga, Ontario 512 (72) Inventor Andrew Skarsgard Canada M3K 1W2 Hawksde, North York, Ontario Il Road 14 (56) References JP-A-62-144918 (JP, A) JP-A-63-109032 (JP, A) JP-A-6-190872 (JP, A) JP-A-8-39612 (JP, A) A) JP-A-6-91696 (JP, A) US Patent 4,883,673 (US, A) US Patent 5,076,637 (US, A) US Patent 5,478,230 (US, A) (58) Fields studied (Int. Cl. ⁷ , (DB name) B29C 45/00-45/84

Claims (21)

(57) [Claims] 1. Two conductive paths which are provided adjacent to an injection molding machine and communicate with each other in a contact area and guide the pressurized molten resin, and two sealing paths which generate an inclined sealing force in the contact area. A sealing device for sealing a contact area between the conduits, and sealing the passage between the two conduits. 2. The sealing device according to claim 1, wherein one of the two conductive paths is a conductive path for an injection nozzle. 3. The sealing device according to claim 2, wherein the other of the two conductive paths is a conductive path for the hot runner manifold adjacent to the conductive path for the injection nozzle. 4. The sealing device according to claim 3, wherein the injection nozzle has a shoulder adjacent to the hot runner manifold. 5. The sealing device according to claim 4, wherein the sealing device is a biasing sealing element that generates a sealing force that is inclined at the contact area. 6. The shoulder according to claim 5, wherein the shoulder has an inner portion adjacent to the passage for the injection nozzle, and the deflecting sealing element generates a large sealing stress on the inner portion of the shoulder adjacent to the passage. The sealing device according to claim 1. 7. The deflection sealing element according to claim 5, comprising a first outer portion having a first thickness and a second inner portion having a second thickness less than the first thickness. Sealing device. 8. The sealing device according to claim 7, wherein the second inner portion has a curved inner portion. 9. The sealing device according to claim 5, wherein the deflection sealing element forms at least partly an angle of 5 ° to 30 ° with respect to the radial surface of the conduit for the injection nozzle. 10. The sealing device according to claim 9, wherein the deflection sealing element is a disk-shaped member. 11. The sealing device according to claim 1, wherein the sealing stress distribution has a peak adjacent to the conduction path of the injection nozzle. 12. A method for sealing a passage between two passages provided in an injection molding machine, comprising: providing two passages for guiding a pressurized molten resin and forming a contact area; Generating an inclined sealing force at the contact area to seal the contact area between the two conductive paths. 13. One of the two conductive paths is a conductive path for an injection nozzle, and the other of the two conductive paths is a conductive path for a hot runner manifold adjacent to the conductive path for the injection nozzle. The sealing method according to claim 12, further comprising the step of sealing the contact area between the two passages with a sealing device that generates a sealing force inclined at the contact area between the two passages. 14. Providing a shoulder on the injection nozzle adjacent to the conduit for the injection nozzle, and arranging a deflective sealing element for applying a sloping sealing force at the contact area adjacent the shoulder. The sealing method according to claim 13. 15. The shoulder includes an inner portion adjacent to the conduit for the injection nozzle, and an outer portion spaced apart from the conduit for the injection nozzle, the shoulder being adjacent to the conduit for the injection nozzle by a deflectable sealing element. The sealing method according to claim 14, further comprising a step of generating a large sealing stress on an inner part of the part. 16. The sealing method according to claim 13, wherein the sealing device is a deflection sealing element which at least partially forms an angle of 5 ° to 30 ° with respect to the passage for the injection nozzle. 17. The method of claim 12, further comprising the step of forming a sealing stress distribution having a peak adjacent to the conductive path of the injection nozzle to seal a contact area between two adjacent conductive paths. 18. The sealing device according to claim 1, further comprising a heat insulating means adjacent to the sealing device. 19. The sealing device according to claim 18, wherein the insulating means is an insulating ring and the sealing device is disposed on top of the insulating ring. 20. The sealing device according to claim 18, wherein the heat insulating means is a heat insulating sleeve used as an extension of the sealing device. 21. Sealing device according to claim 18, wherein the thermal insulation means is a sheath or a solid sleeve mounted on the nozzle housing outside and / or adjacent to the sealing device.